Are you looking for a less cantankerous, more shareable version of this video? The condensed version on Connextras has got you covered! ukposts.info/have/v-deo/l5hyqYGrpoipq30.html

I like to imagine Alec is talking to an HVAC rep who's sitting tied up across from him. It makes the video so much funnier

How fitting that Alec is just about the only UKpostsr who puts the long version on the _main_ channel, rather than saying "here's a bite-size video - for the full-length, go to the second channel"

"Maybe you think that's strange, but I think I'm strange too." ...This encapsulates part of the reason I like this channel.

Former HVAC sales rep here. Great video! While attending a hvac training, I was giving a rather shocking Stat, less than 10% of hvac sales in 2022 had a load calculation preformed prior to the sale of a new system. I'm not innocent either, as I was never told what or how to preform one of these and became part of the problem. The more I learned in that role the more shocked I was at how much damage and headache I likely caused for homeowners. Your comments on the lack of communication between departments is actually rather accurate and something that has, as of late become a much bigger focus for the company. (who I still work for under a different position, in another trade department) so atleast at our national company things are changing and loadcalcs are becoming a much larger focus company wide. The issues of system sizing has been a regular cause of issues, callbacks, and heachaces for us and the customer.

I won't bore everyone with the saga, but trying to find an actual pro HVAC installer in a major market that understood this stuff and was willing to work with me took over a year and too much of my life energy.

One of my favourite things about heat pumps: My parents regularly used the old cliche line of parents telling their kids to close the doors / windows, "we aren't air conditioning outside". And now they aircondition the outside for half the year.

Whew, he almost missed the nice on 69 but stopped himself. You are quite literally the Project Farm of the electrical side of youtube. Your tests are always so indepth and well logged and you come up with creative ways of running these tests.

Michigander here, i LOVED the hard flex on midwesteners having those most common sense for the past 100 years. my house is 100yrs old and guess where my vents run??? THROUGH THE WALLS

Is this the ultimate Technology Connections video? Combining space heaters, with extension leads, with incandescent Christmas lights, with heatpumps and the latent heat of vaporization? Like a call back to every previous video.

As someone in the HVAC Trade, this video is extremely valuable to homeowners and you are empowering my own standards. Not only that, you are calling out the predatorial practices of HVAC Companies. Heat pumps are amazing tech, and I would cite this source 7 days of the week. Fantastic breakdown, thank you!

I work at an engineering firm & design HVAC systems every day. You hit the nail on the head! Every time i thought “well what about x” you would say “on the other hand -“ its like you were reading my thoughts. Great video!

As a Canadian, I absolutely grok your midwestern rant about the placement of ducting and vents. The spaghetti octopus in the attic gave me the giggles.

HVAC guy here. A lot of the issues I've seen have been lack of adequate training. I've literally googled my way to competency, and that is completely unacceptable. But, they don't care as long as we figure it out eventually because the customer is footing the bill anyways. It's horrifying

Am HVAC design engineer (floor plan layouts not the actual units), one of the reasons why gas furnaces are always oversized is because that 60k BTU is the smallest many manufacturers make, and they end up being the most common/cheapest because they're used on everything 5 tons and under. To get a smaller heater, you basically have to go electric or heat pump

As a hvac tech. We do load calcs on every single sale (except mobile homes). We fit to the home but upsize the coil a half ton to dehumidify a little more. We're also trying to get into insulation to help our installs work more efficiently so this video was awesome to listen to

HVAC guy is coming out this afternoon to discuss replacing my house's 15 year old AC/Gas Furnace combo. As a fellow midwesterner I was already planning on getting a heat pump specifically due to your previous video, but it was nice for this one to pop up today and give me a reminder.

This UKposts channel has made my plans for a mega-mansion _really_ weird.

I haven't bought a dishwasher pod in over a year. I couldn't be happier about knowing how dishwasher detergent works. So i will be watching this entire show from beginning to end.

Just wanted to say it's been amazing to watch this channel grow in size, success, and technical polish, without budging a millimeter from its principles, its tone, or its sense of humor. Keep up the excellent work!

That rant was glorious! "You probably think this video is about you" 😂

1 hour video from Technology Connections? It just became movie night! Always a treat.

As a 45 year veteran HVAC company owner, you made a GREAT episode! Also, the pith was outstanding!

Thank you for stopping and adding the obligatory "69, nice" as is customary proper internet etiquette. Love all your videos dude, you are inredibly thorough.

Software engineer here. If someone specs the Manual J Calculation thing, I'm sure I could code it. Thanks for another great and interesting video, Alec!

I am a HVACR professional and I now train others in the HVAC industry. This is solid gold. I strive to instill in my trade that we have been constantly oversizing equipment for as long as the trade has been around. I converted to what is called a dual fuel setup about 10 years ago that is a heat pump with gas backup heat (lots of boring details as to why I went with that setup) When I bought my house it had a 120,000 btuh furnace installed. I now heat the house with a 3 ton heat pump which matches the cooling load on the home it is matched with the smallest furnace I could get that can provide airflow for the HP and has the capability to operate at 40% of its rated capacity. I live in a cold weather climate and with some minor help from the furnace on that colder than cold day once In a while it keeps my home very comfortable. Using similar thermostat technology I can track my power and gas usage and typically my furnace runs less than 15 minutes per day most days. And that runtime is almost all when the heat pump is defrosting. My area has incentives from various agencies and organizations will completely if not more hand cover the equipment cost to the contractor for the cost differences in the equipment from AC to HP units. Installation cost differences given modern thermostats is almost $0 A lot of what someone people will call out as flaws in his analysis are not reading between the lines in his data and methodology. You simply cannot give a masterclass on absolutely everything that goes into this stuff in one hour! Some details are left out. Great video Anyone who says otherwise is definitely selling something

You got a mention on HVAC overtime over this video, HVAC professionals agreed with you by and large. Good point well made Alec

I love your sass on the whole ductwork rant. It cracked me up. As a Michigan resident I salute you sir!

I’m a HVAC salesperson in the DC Maryland Area. Old oversized equipment is so prevalent here. And you can take your time explaining to the customer why it’s oversized, but when you have customers who say why change it if it’s worked for all these years and other salespeople just spec what they had. I did that to a customer…had a 3.5 ton ac and a old 150k furnace from the 40s…i put a 70k furnace and 24k heat pump. Row home about 1800sq ft. Customer kept bringing up how this website was saying he needed 4k…we installed it, he loves it. Great video!!

The delayed "nice" absolutely took me out with laughter. Was not expecting that, but I am absolutely here for it

I'm at the 30-ish minute mark and the volunteer firefighter inside me just cringed really hard... Last night, we had a fire call where someone plugged a space heater into a power strip, burned up the strip, and nearly burned up the outlet... Thankfully no actual fire occurred. Thank you for knowing what you did was unsafe and warning others not to attempt it themselves. Science can be fun but dangerous at times. Love the content.

You absolutely hit the nail on the head with your criticism of the separation of sales and technicians. While a tradesperson’s primary job is installation and maintenance, not “closing deals” their technical knowledge is utterly necessary to ensure each customer gets what they need. If you ever, EVER want to know what you need, talk to someone who does the actual work and is clearly passionate about what they do.

Man I feel you about the "inside" unit in the attic. My home is built this way, along with *all* the ductwork going through the uninsulated attic. They even stuffed the water heater up there, so that when it inevitably springs a leak near the end of its life, you get to come home to your ceiling now being on the floor!

As a HVAC service tech I have know this for over 50 Years. I was asked to design and install a new furnace and A/C system in a house which was having an addition added. The addition was almost 2000 Sq Ft. The house was built in the 60's had a large furnace 160,000 BTU. I did a precise heat load calculation and added a multi zone damper system to the new furnace. The new furnace was 125,000 BTU 95 percent. The town inspectors said I was wrong and forced me to provide the calculations. They OK'd the system a month later. and it ran great.

I love this dude, he's one of those youtubers where after you watch one video you're hooked. Also thanks to him my dishes are cleaner than ever.

I have a 2400 square foot home that was built in the 50’s and is insulated in the loosest sense of the word. I replaced our radiant boiler with ducted 4/5 ton heat pump system (I did all the work myself). My manual J put me at around 42000 btu loss so I got the bigger unit which can be switch to 4 ton mode for higher efficiency. It’s has never let me down in the northern Michigan winters where sub zero temps are regular. I have 10kw heat strips which I've never needed as backup, but they do run during defrost cycles to keep the air warm while the fan runs. this was our 4th winter with the system and i have no regrets.

Thank you for solving a mystery I've had in my two year old home since I moved in! I've been wondering why my bedroom in the nice, new house hasn't been able to stay warm enough without space heaters and just haven't had the time to investigate. Thanks to your rant I now know to look at the ductwork in the unheated basement as a probable source of the problem. It's so helpful to have a reminder that I'm not imagining things.

As a (former) licensed HVAC installer and technician, I want to thank you for giving this industry a stern talking to. I did load calculations for my jobs and there was a (short) time where the state required them for every final inspection, but that was abandoned because few of the HVAC people here are intelligent enough too do basic math :(. I'm not not kidding as they also had to seriously dumb down the state licensing test in a desperate attempt to help these idiots pass, despite requiring them to have all applicable code books with them during the test! There was such a shortage of licensed workers that homes could not be built and I imagine this has only gotten worse. Thankfully, I do know of local HVAC companies that are qualified and very good at their job, but I also know of some that are both incompetent and debatably criminal as they'll overcharge their own mother and then brag about it to other contractors. Informing consumers of these issues is very valuable, so thank you. This is perhaps the most important HVAC-related video you've done since the one on stupid portable air conditioners.

I feel like 29:37 "Through the magic of buying..." was the payoff of one of the longest setups in history. Well done.

HVAC professional for 35 years. You are on the money. Plus installing even a like-sized high efficiency syatem on old restrictive duct work completely negates the benefits of the new equipment. I'd say 90% of the equipment out there is grossly oversized.

Long videos are great as long as they're adequately packed with information

"The house didn't burn down" - now that's a motto I can live by.

I live a little further north than you and basically got this lecture from the HVAC professional I had out to estimate replacing my furnace and ac. He said their standard is to determine requirements and then double it because if they don't people get bothered when the house doesn't heat up immediately in the morning, but he recommended going with the minimum if I was comfortable with the reality. He also said if I wanted to save money I should have a home energy audit and then act on all those recommendations first. Thank you for spreading the word.

I really appreciate the way you split this video up and put it on the other channel, I for one would still be excited for this video if it was twice as long and even more in depth, but I've been looking for a way to get my dad interested in your channel and the condensed version might be exactly what I need for that

i realy like these detailed and long videos. since i can stop at any time and continue when iam ready for it again 👌🏾😎 thank you!

As someone with ADHD who struggles to focus on anything for very long, Alec is one of the only UKpostsrs who can make a 1+ hour long video on literally anything and keep me hooked the entire way through

I was loving this video completely the normal amount (which is already a lot, given this channel) but when the holiday lights came out, that was a +3 smile bonus immediately 🎄

Hey man I just wanna say you are a daily part of my day I watch you every morning with my morning coffee thank you.

We always enjoy your insights! We had a heat pump installed on Feb 29 - inspired by the way you interpreted the technology some time ago. This was hybridized with our 2021 HE gas furnace. We get an $800 carbon rebate each year (Canada) - and Ontario's electricity supply is quite low in carbon production. We're not expecting to make money (net), but we'll be content because we are reducing our carbon emissions. With wind turbines to the south, solar installations to the north and a new natural gas 'peaker' plant to the west, the future of energy is always on our horizon. Thanks for all the effort you put into your productions! David, Amherstview, Ontario

It was a smart thermostat that led my dad to discover someone was stealing heating oil from his business. A locking cap solved that problem - he has since ditched oil altogether.

Ah yes, an hour long video full of dry humor and technical information, my favorite!

Love watching your posts. Always great quantitative and qualitative statements and outcomes. I remember when installing an HVAC in a home that wasn't HVAC to start asking the rep to be sure it was PROPERLY sized and not just guestimated. He spent the time measuring and covering the house, settling on about a 2.5 Ton HVAC system with heat pump. All comparable homes were 5 tons for some reason. I said I wouldn't pay for anything we didn't need and to prove out the math... this was in the 90's. That house maintained 70 degrees year round just fine for me. Best investment I made at the time along with the new properly installed well with pressurization, hardness management, and 5 stage filtration. (Unlike the old system which was well direct water on demand with no pressurization).

Again another great video. Thanks Alec, your fellow energy engineer. I really appreciate the sizing examples.

I gave up trying to find an HVAC company that wasn't going to lie straight to my face about heat pumps, so I installed it myself.

Energy auditor here, only 4 minutes into the video but you named off everything on my residental energy audit software. I check everything from the joist spacing to the operating pressures of each register. The Department of Energy are using all the factors you listed in order to weatherize homes. Hope that gives you peace of mind. One of my goals is switching gas furnaces to electric heat pumps. Western Ky here. You hit such a huge point at the 25 minute mark. The software we use has a Windows XP face and I think it came out in 2012 and just had updates. I've got a list of DOE approved audit softwares, and they're all a decade and a half behind us. We need to take some of that weatherization money and use it to design a user friendly app, if not just for the professionals. The current system is frustrating enough to make me find another job. On the ductwork design rant; almost every house I inspect here has the ductwork in the attic. We spend a few hundred on sealing the ducts with mastic on every job. Concerning your garage, is the ductwork in that chase internally lined with insulation? Maybe that could help.

Just checked my data from the same cold snap. my furnace was still under 12 hours for the day. It was also far colder here and we were home with the heat at a higher setpoint. Looks like once this dies, ill be able to size a smaller unit here too (which I already was planning on) Love the well informing videos on this stuff. Keep it up!!

Bro really almost burned his house down just so he could make an hour long video about AC. I love it.

Hearing you talk about Manual J calculations warmed this old HVAC guy’s heart. Thanks for a great video.

Pro tip: share a wall with someone who likes to keep their house _way warmer_ than you prefer. I used to live in an apartment where I shared all my walls and I never turned on my heat.

For the people in cold climates complaining about how heat pumps won't work in winter, get a cold climate heat pump. And seal any cracks so the heat won't escape. It's that simple.

Great video and very well put together. Heat pumps are certainly a great way forward. One of the main challenges I've seen is how to go from a system reliant on a log burner, or a gas boiler and radiators to a heat pump. Specifically how to distribute the heat in a property not designed with ducting in mind and where such a solution can be rather expensive and complex. Still, the long term savings and day to day savings make the argument for heatpumps very hard to ignore. Especially where solar could be used to augment or cover the electrical running costs of such a system.

I've been in this trade for 35 years, when I do a manual j, I find the existing heating systems are usually around 33% to big. I have lost several heating system replacements, because the customer say I'm under sizing their system. Because all the other companies said you need to go with the same size. The HVAC industry has its problems, but homeowners like bigger systems in their house. So we either conform, or we die in the wind.

Fortune Teller: -I see a small townhouse. -I see you with extension cords and a lot of space heaters. -Jesus that's a lot of space heaters.

Your snarky comments, plus my interest in the topics you cover, are why I love this channel!! Never give up the snarky.

So true Alec, I have run my company for the last 20 years, but my dad when he ran it was steadfast with the square feet per ton rule for Hvac sizing. The manual J load calc along with the manual D ductwork design, really proves the home load.

I work in the HVAC industry and appreciate all of the videos you have made on heat pumps. I have always been impressed with the enormous amount of research you have put in as a consumer. I would love to sit down and have a couple hour chat with you on the subject, just because my own hubris makes me believe I could fill in some tiny and I do mean miniscule gaps in your knowledge. But I will say this, there is no reason to wait to install a heat pump, if you currently have a 2 ton A/C, there are units on the market that will allow you to simply change the condensing unit outside and nothing else and have a 20+ SEER heat pump.

“avoid complaints”. You finally got there! I design heating systems and you are 100% correct; across the board. You only understate the power of whining, relentlessly unsatisfied and miserable complainers.

Thanks for the video. It's interesting to learn what do you use to keep your houses warm on the other side of the Atlantic. In my place of the world (eastern Europe), radiator-based and floor heating systems are way more common than airduct-based ones. We pretty much only use airducts for ventilation systems, rarely for heating. In my house I have a heat pump that includes automatic electric backup (and even a built-in water heater). The electric backup only runs in really harsh conditions (like -18-20 celsius outside). For backup, we do have a fireplace which is piped to the same circuit, which means the heat pump's electric backup shuts off automatically it detects another heat source. This fireplace used to be the main heat source before we got the heat pump installed. Nowadays, it's mostly used to burn paper waste. My system is only slightly oversized (if at all), there's no trend to install oversized heating systems in my place of the world, because it's pretty hard to do with radiator and floor based systems. Well, unless you install way too many radiators.

Really insightful video, Alec. My wife and I bought a home in Madison, WI about a year ago, and I have been trying to figure out our HVAC situation. As far as I can tell, our furnace is either perfectly sized or slightly undersized, but the default setbacks on Nest thermostats are ridiculously aggressive.

this channel has armed me with all the knowledge i could ever need for the house i will never own

The whole 'Heat pumps are just air conditioners, but they don't want you to know!' part made me chuckle a little. Down here in Aus, they've just been called 'reverse cycle air conditioners' for as long as I can remember, so there is no big mystery.

This video pushed me to learn my furnace is about twice what i need! That explains the fire that comes bellowing out

Always stoked for your deep dives. Wish I'd known all this before the most recent HVAC work. As a fellow midwesterner and science guy I'm still kicking myself for getting swindled and relying on too much gas.

1+ hour Technology Connections episode? Hell yes! I hate it so much when someone tells me we're going to do a 'deep dive' on some subject and then can only muster like 25 minutes of content.

Your point on sales being separated from installs and service is so on point. It’s happening to every industry though, HVAC, plumbing/water treatment ,automotive , Electrical, and telecommunications.

I was a hvac contractor and I agree with this video 100%

Oh the snark! I love it. Thank you sooooo much!

To someone who’s watched every video on this channel, this video is like friggin Infinity War. All the old favorite characters make an appearance, all it’s missing is some painted white LED Christmas lights! Edit: Jesus Christ, I was only halfway through and I was joking about the Christmas lights. Touché, Mr. Connections.

"These allowed me to control the space heaters, and Christmas lights, with precision" - great phrases of our time.

Just purchased mini splits for my entire home partially because of this video series. I live in the PNW and do not have central AC I also use baseboard heat so they will dramatically lower my heating bill.

9:02 - "Oversized" means the energy needs are greater than it's losses? You WANT an oversized furnace then, so it can BEAT your needs, and has to run less often -- which means great durability and hence less issues with it breaking (it running less is less wear and tear).

I'd like to take a moment to note that I really enjoyed the "you're so vain" joke, it was delightful.

This closet conceals an entire FURRRRNACE!

I find myself continuously amazed by the fact that people in North America are fine with paying north of $200,000 for a house made of wood. Insane.

Same situation with my house in northern NH. The heat pump I had installed is a dual-head 18,000 btu/h unit and has no trouble keeping the little single-floor house nice and warm despite the -20 degree temps outside. The oil furnace that this replaced was a 120,000 btu/h furnace (with the ductwork in the attic and crawlspace, your favorite :D ). There weren't many times that it ran for more than just a minute or two before shutting off for 10 minutes. Not a short-cycling issue, just that it doesn't take much to heat a 900 sqf house.

A tale from Denmark🇩🇰 Changing from gas to HVAC, I’ve calculated 6 kw needed. Asked for quotes in HW price, extras and man hours. Took me 12 quotes with 8-16 kw pumps, before one supplier, 200 miles away made the right quote with 7 kw HWAC. You’re so spot on the problems, and not alone. 🇩🇰😎

I absolutely admire your commitment and dedication to consistently spelling out "H-V-A-C" every single time instead of just saying "H-Vac" like everybody else does.

Fantastic work sir. Well done

What a timely video. I just did a version of your experiment. I work on chillers and bulk milk tank coolers owned by dairy farmers. I have been thinking about my next air conditioner/heat pump/furnace. I live in a home built in 1879 or so. I have replaced all of the windows, siding, and insulation. When I moved into the house 40 years ago it had a 100,000 Btu furnace that couldn't keep up on the coldest three or four days of the year. 20 years ago, after some of the insulation upgrades, I replaced this with a 60,000 Btu furnace. This past January, during the same cold snap you used for the video, I installed temperature probes in the supply and return air ducts and sat with a stopwatch and figured out that my natural gas furnace burner was on 2.5 minutes out of every 13 minutes while the outdoor temperature was minus 21 degrees F. And the house was comfortable. I learned that my home improvements have now made my furnace is five times bigger than it needs to be. I will probably go with a heat pump that is 1/4 the size of my existing furnace for the reasons you mentioned. I would like to be able to catch up a little if it gets behind for some reason. I love your videos...keep up the good work!

Totally unrelated to the video topic, but my husband wanted to watch this video with me so he asked me if I wanted to watch 'the guy with the brown' and I knew what he meant 😂

The subtle “you’re so vain” joke at 46:54 is one of my favorite from you… great video. As usual.

That Carly Simon reference gave me a good chuckle. I always appreciate your witty writing and dry humor.

I installed my own 5 ton heat pumps. Yea that’s right 2 of them! I have a very big house. I never installed a central air before. It was a lot of work but pretty easy. They have been rocking for over a year… when it’s -10 out it’s warm and toasty inside. Ac freezing cold air. Love it.

Just a side note for people: here in the Southeast we use heat pumps all the time, so the "HVAC industry" is very location dependent. This channel is very Midwest (and Northeast) oriented, not that there is anything wrong with that (Seinfeld reference lol)

That hour went by so quickly. I literally thought: What, it's over already? how can one person explaining HVAC be more entertaining than all of Hollywood combined?! Thank you so much Alec! 🤗

Mechanical Engineer here. I work in the HVAC industry at a MEP firm. We ALWAYS provide load calculations (Manual J,S, and D) and also Energy calculations on a dwelling. Not only is this mandated by jurisdictions but DOE enforces it as well. The real issue is the owners and developers they want to pass the cost to the consumer. The industry of multi-family housing is especially bad with the cheapest materials being used and the routing of systems being done the fastest and cheapest ways. Great video!

I think there’s a few other things that are taken into account: • longevity of the equipment (high duty cycles cause faster wear) • overspeccing for lower efficiency as the unit gets older • not knowing the insulation value for the house (hard to do) • overspeccing for margin • hvac planners not knowing how to calculate things and just going at the charts like a bible or just not caring

"But you may have noticed the runtime" *moves mouse over the video and is shocked by the runtime* "Yeah, we're covering a lot" That... was a very nicely timed pause there. At least it was for me. 🙂

Fun fact: in Australia we call them "reverse cycle air conditioners" Except Tasmanians.

Very interesting! Thank you so much for all the information! I think one reason an HVAC contractor might over size is due to large variations of construction quality. Small defects could add up quickly and then you are back at a house upgrading equipment on your dime. That's where the historical data you mentioned would be handy. Unfortunately, there are probably some contractors using larger units as a way to boost profit margin on already tight jobs.